Knife-blade switch



A. H TRUMBULL.

KNIFE BLADE SWITCH.

APPLICATION man JUNE 11, 919.

1 AQ4,6 6. Patented Aug. 1, 1922.

% F fi- Ffi 1 m F 55 MUN" t I NW1 Y \lillhl IHHII /6 /6 k MTNESS IATTEIR NEY ion-twin ALEXANDER H. TEUMBULL, OF STRATFORD, CONNECTICUT,ASSIGNOR TO THE CON- NEC'JZICUT ELECTRIC MANUFACTURING COMPANY, OFBRIDGEPORT, CONNECTICUT,

A. CORPORATION OF CONNECTICUT.

KNIFE-BLADE SWITCH.

Application filed June 11, 1919.

T0 aZZ whom it may concern.

Be it known that I, ALEXANDER H. TnuM- nULL, a citizen of the UnitedStates, reslding at Stratford, county of Fairfield, State ofConnecticut, have invented an Improvement in Knife-Blade Switches, ofwhich the following is a specification.

This invention relates to electric circuit closers or switches and hasfor its objects to provide a knife blade switch which may be operatedfrom its hinge end by a-handle member located at a distance from theswitch terminals, said switch having provision for completely insulatingthe operating means from the current carrying portions of the switch,requiring but a single contact member for cooperation with each switchblade to open or close the circuit, and being of a generally improvedconstruction atfording a smooth and easy action and permitting the readyassembling and disassembling of the parts; and also'to provide animproved multiple unit switch device in which the successive throwing ofa plurality of switches in order to open and close a plurality ofcircuits is facilitated.

The foregoing and other objects of the invention. together with meanswhereby the same may be carried into effect, will best be understoodfrom the following description of certain forms or embodiments thereofillustrated in the accompanying drawings, in which:

Figure l is a plan view otf the casing of an enclosed switch constructedin accord ance with the invention.

Figure 2 is a side elevation with the easing partly broken away, theswitch being shown in circuit breaking position.

Figure 3 is a plan view with the casing cover removed and the switch inone of its circuit closing positions.

Figure 4 is a transverse section taken substantially on the line l4,Figure 2.

Figure 5 is a detail View of one of the switch hinges.

Figure 6 is a detail view of the construction at the point where theoperating shaft enters the casing.

Figure 7 is a plan view of a multiple switch embodying the invention.

Specification of Letters Patent.

Patented Aug. 1., 1922.

Serial No. 303,367.

Figure 8 is an elevation of the parts shown in Fi ure 7.

Referring first to Figures 1 to 4, the in vention is therein illustratedas embodied in an enclosed switch particularly adapted for use inconnection with a junction box. As shown in said figures, said junctionbox comprises a body 15 having a hinged cover 16 and enclosing a blockor plate 17 of insulating material constituting the base of the switch.Seated at their outer ends in alined openings in the opposite walls ofthe body 15 are a pair of alined insulating sleeves 18, spaced apart attheir inner ends for a purpose presently to be described. Rotatablymounted in the sleeves 18 is a shaft 19 of hexagonal or othernon-circular cross section hzwing, outside the casing, an end portion 20which is bent at right angles to the rest of the shaft to constitute anoperating lever, and which is provided with a handle 21. Mounted on theplate 17 immediately beneath the sleeves 18 is a pair of terminals towhich circuit or line wires 67 may be connected, each of said terminalshaving a pair of spaced parallel arms 23 formed with alined openings toreceive and support a bushing 24 on the corresponding sleeve 18. Mountedon each of the bushings 2% between the corresponding arms 28 is a switchblade 25, said switch blades being connected intermediate their ends bya block 26 of insulating material, the ends of said block being securedto the switch blades by an 'ular brackets 27 riveted to said block andblades respectively. The block 26 is provided with an opening whichloosely receives the end of an arm 28 mounted on the shaft 19 betweenthe spaced inner ends of the sleeves 18, said arm having an openingshaped to [it the shaft 19, whereby said arm is secured to said shaftfor rotation therewith while permitting longitudinal movement of saidshaft with respect to said arm. The outer ends of the switch blades 25are, in the construction shown, adapted to cooperate alternatively witha pair of contacts 35 or with a pair of contacts 36 when said switchblades are turned in opposite directions from the neutral or circuitbreaking position shown in Figures 2 and 4. The contacts connection withcircuit or line wires 65 and The switch may, if desired,

66 respectively.

operation,

be v retained against unauthorized in the position to open the circuitby means of a suitable seal'orlock 31 (see Figure 4) passed around theoperating portion of the shaft and engaged with an apertured bracket 32riveted or otherwise secured to the exterior-of the casing body 15.

As will now be seen, the switch blades are supported, independently ofthe shaft I the hinge arms 23, and are completely insulated from saidshaft and from the arm 28 by the sleeves 18 and insulating block 26, sothatno current can pass from said blades to said shaft. I Said switchblades are, however, 'op'eratively connected with said shaftyfor"operation thereby to open andclose the circuit, by means ofthe arm 28andblock 26, said blades turning about an altis'coincident with-the axisof said shaft but being separated from said shaft by the interposedsleeves18, which are independently supported by the arms 28 and thewalls of *the casing 15.

Theshaft19 is held in place invthe sleeves 18 by cotter pins 33 betweenwhich and the adjacent sides of the casingbody 15 are interposed springwashersBe-each comprising a'c entral portion'toengage'the cotter pin'33, and havingan opening to receive the shaft, and'a plurality of armsoffset from the pla'netof the central portion to engage the casing.These springsv serve to hold the shaft properly centered and to give asmooth action thereto and also serve to ground said shaftnpon the casingin order to carry away any current which may accidentally reach the samenotwithstanding the insulatingprovisions above described, 1 It will beseen that, by removing-the cotter pins the shaft 19 may readily bewithdrawn longitudinally from the sleeves 18 and arnr28, and the latter,due to its loose engagement with the opening in the block 26, bethereafter removed from between the sleeves 18, thereby easilydisassembling the parts which may be as readily assembled inproper'position by reversing theseoperations, no careful positioning ofsaid parts, other than that naturally accompanying the assemblingthereof, being in qiii itldi i I above stated, the blades are, in theconstruction shown, adapted-to closethacircnit either between theterminals 22 and ter minals 29 or between the terminals 22 and theterminals 30, althouglnfifor some pur poses, one of'the terminals 29,01130 may be omitted. In any case, however, it will be seen that saidblades are obliged to engage and disengage but one pair of contacts 35or 36 in order to make or break the circuit,

said blades being permanently electrically connected through theirhinges with the terminals 22, this permanent connection beingpermittedby the complete insulation of said blades from the operatingshaft and other parts of the device. Extended contact surfaces areprovided for, the passage of current from the arms 23 to the blades 25,and, in order to maintain these surfaces in close engagement, each ofthe bushings 24 is preferablyiformed with end flanges 37 between one ofwhich and the adjacent arm 23 is interposed a spring washer 38 (seeFigure 5) similar to the spring washer 34.

In Figures 7 and 8 is shown a multiple unit switch device constructed onthe gen oral principle of the single unit switch above described andcomprising a shaft 39 on which are mounted two pairs of switch blades 40and 41, each pair being substantially similar in construction andmounting to the switch blades' 25 and therefore not requiringdescription'in detail. The blades lO cooperate with terminal contacts42, and the hinge terminals 4:3 thereof are shown as connected. by fuses4a with terminals while the switch blades 41 cooperate with terminalcontacts 46 and the hingeterminals a7 thereof are connected by fuses 48with terminals 49. The terminal contacts 42 and 46 aredisposed atopposite sides of theshaft 39, and the operating arms 50 andofl for theswitches e0. and't-l respectively are disposed in different angularpositions on said shaft, said arms "being herein shown as disposed at anangle of 90 fromone another. It will therefore be seen that a movementof the shaft 39 through an angle of 90 will serve to open the switch4t() and close the switch 4:1 or vice versa. This arrangement isparticularly advantageous for use under circumstances in which it isdesired'to close oneswitch and thereafter open said switch andimmediately close another, as, forerample, in starting a polyphasemotor, since, by suddenly throwing the handle 52 from oneextremeposition to the other, one of the switches may be opened and theother immediately'closed without an appreciable interval. In order tofacilitate this operation, as well as to serve as a convenientindication of the position; of the switches, the

operating portion 53 of the shaft 39 preferably occupies-an angularpos1tion half way betweenthe arms 50 and 51, being disposed at an angleof 45 from each, so that'an inclination of the handle in one directionfroin a vertical position will 'indiiate the closure of the switch40fwhile a similarinclination in the opposite direction willindii'ateaclm sure of the switch 41, saidhandle being in a verticalposition when both switches are The apparatus shown in Figures 7 and 8is illustrated as inthe form of an unen- 1 season closed switchmechanism comprising a suit able switch board or insulating base 5%,upon which the several terminals above referred to are mounted, andprovided with a pair of brackets 55 constituting bearings for the shaft39.

l-laving thus described my invention, I claim:

In a knife blade switch, an insulating sleeve, a shaft mounted to turntherein, a switch blade mounted to turn about said sleeve, and means foroperatively connect ing said shaft and blade.

2. In a knife blade switch, an insulating sleeve, means for supportingtee same, a removable shaft mounted to turn in said sleeve, a switchblade mounted to turn about said sleeve, and means for operativelyconnecting said shaft and blade.

3. In a knife blade switch, av pair of alined insulating sleeves, meansfor supporting the same, a shaft mounted to turn in said sleeves butlongitudinally removable therefrom, a pair of switch blades mounted toturn about said sleeves respectively, an arm between said sleeves andconnected with said shaft to turn therewith but disengageable therefromwhen said shaft is withdrawn from said sleeves, and means for connectingsaid arm with said blades.

l. In a knife blade switch, an insulating sleeve, a shaft mounted toturn therein, a bushing on said sleeve, a switch blade mounted on saidbushing to turn about the axis of said shaft, and means for operativelyconnecting said shaft and blade.

5. In a knife blade switch, an insulating sleeve, a shaft mounted toturn therein, a switch blade mounted to turn about said sleeve, andmeans for operatively connecting said shaft with and insulating the samefrom said blade.

6. In a knife blade switch, a pair of alined insulating sleeves, a.shaft mounted to turn in said sleeves, a pair of switch blades mountedto turn about said sleeves respectively, an arm between said sleeves andcon nected with said shaft to turn therewith, and means for connectingsaid arm with and insulating the same from said blades.

7. In a knife blade switch, a shaft, a switch blade, means independentof said shaft for supporting said blade through which the shaft extendsso that the blade will turn about said shaft, and means for operativelyconnecting said shaft with and insulating the same from said blade.

8. In a knife blade switch, a shaft, an arm thereon, a. switch blade, amounting on which the blade is pivotally supported and through which theshaft extends so that the blade will turn about said shaft, and a. blockcarried by said blade and having an opening engaged by said arm.

9. In a knife blade switch, a pair of alined insulating sleeves, a shaftmounted to turn in said sleeves, a pair of switch blades mounted to turnabout said sleeves respectively, a block connecting said blades, and anarm between said sleeves and connected with said shaft, said armengaging said block to operate said blades.

10. In a knife blade switch, a pair of alined insulating sleeves, ashaft mounted to turn therein but longitudinally removable therefrom,pair of switch blades mounted to turn about said sleeves respectively,an arm mounted on said shaft between said sleeves, said arm having anon-circular open ing and said shaft having a non-circular portionremovably engaging said opening, and a block connecting said blades andhaving an opening engaged by said arm.

11. In a knife blade switch, a shaft, a switch blade mounted to turnabout the axis of said shaft, an insulating sleeve interposed betweensaid shaft and blade, an arm on said shaft, and an insulating blockcarried by said blade, said block having an opening engaged by said arm.

12. In a knife blade switch, a switch blade, means for pivotallysupporting the same, means for conducting electric current to saidsupporting means, said supporting means and switch blade beingelectrically connected, a. shaft disposed with its axis co incident withthe axis of movement of said blade, insulating means between said shaftand blade, and means for operatively con necting said shaft and blade.

13. in a knife blade switch, a support, a shaft journalled therein, aswitch blade operated by said shaft and insulated therefrom, and aspring washer carried by and contacting with said shaft and engagingsaid support.

ll. In a knife blade switch, a support, a shaft iournaled therein,insulating material between the shaft and the support, a switch blademounted to turn about said shaft and operated thereby, means forinsulating said shaft from said blade, and means for grounding saidshaft on said support.

15. In a knife blade switch, a terminal having a pair of supportingarms, a bushing carried by said arms, an insulating sleeve in saidbushing, a switch blade carried by said bushing between said arms, acontact cooperating with said blade, a shaft mounted to turn in saidsleeve, and means for operatively connecting said shaft and blade.

'16. In a knife blade switch, a pair of terminals each having a pair ofsupporting arms, alined bushings carried respectively by the arms of theseveral pairs, insulating sleeves in said bushings, a pair of switchblades each carried by one of said bushings between the arms of thecorresponding pair, a pair of contacts cooperating respectively withsaid blades, a shaft mounted to turn in sleeves, an insulating blockconnecting blades and provided with anopenmg,

said

and an .arm on said shatt between said shalt, contacts disposed atopposite sides of said shaft, switch blades'cooperating with saidcontacts respectively, and operating members for said switch bladescarried by said shaftand disposed in diiierent angular positions aboutthe axis thereof, said switch blades rotatably carried by supportsindependent of said shaft. V i

18. A multi le unit switch comprising a shaft, contacts disposed atopposite sides of said shaft, switch blades cooperating with saidcontacts respectively, means for pivotally supporting said switchblades, means for conducting electric current to said supporting means,said supporting means and switch blades being electrically connected,operating members "for said switch blades carried by said shaft anddisposed in different angular positions about the axisjthereo'l andmeansfor insulating said shaft from said switch blades.

,19.A multiple unit switch comprisimig a shaft,contacts disposedatopposite sides of said. shaft, switch blades cooperating, with saidcontactsrespectively and independently m sses supported to turn abouttheaxis of said shaft, and open ing members for said switch bladescarried by said shaft and disposed in different angular positions aboutthe axis thereof. a 20. A multipleunit switch comprising a shaft,contacts disposed. about the axis of said shaft, switch bladesco-operating with sa 1' contacts respectively and independentlysupported to turn about the axis of said shaft, and operating membersfor the switches carried and rotatedby said shaft.

A multiple unit switch comprising a shaft, unitary switches disposedabout the axis of said shaft and mounted independently thereof,operating members tor. the unitary switches married and rotated by saidshaft, and means for insulating said. shaft and operating members fromthe current carrying portions.

22. A multiple unit switch comprising a sliattt, contacts disposed aboutthe axis of said shaft, switch blades cooperating w th said contactsrespectively and independently supported to turn about the axis of saidshaft, means for insulating said shaft and operating members from thecurrent carrying portions, and operating members forthe switcl'iescarried and rotated by said shaft. In testimony whereof I atlix mysignature.

ALEXANDER nTn MsnLL;

